1. Field of the Invention
The present invention relates to a resin sealed ceramic package and to a semiconductor device and, more specifically, it relates to a resin sealed ceramic package for resin sealing of mounted semiconductor elements, and to a semiconductor device wherein a semiconductor element mounted on a ceramic package is resin sealed.
2. Description of the Related Art
Conventional ceramic package-mounted semiconductor elements have been hermetically sealed with metal caps and the like.
However, attempts have been made at resin sealing semiconductor elements mounted on ceramic packages in order to achieve lighter weight and a lower cost of the semiconductor devices. In particular, for semiconductor devices on which CCDs (Charge Coupled Devices) are mounted, when the CCD is hermetically sealed by a cap fitted with a glass section it has been extremely difficult to achieve perfect sealing between the cap and the glass section and between the cap end face and the ceramic package end face.
As shown in FIG. 10, a semi-transparent sealing resin 106 can be used for resin sealing of the CCD 104 mounted in a cavity 102 of the ceramic package 100.
As FIG. 10 shows, the resin sealing of the CCD 104 mounted in a cavity 102 of the ceramic package 100 using a sealing resin 106 allows the CCD to be more easily sealed than when the sealing of the CCD is accomplished with a cap fitted with a glass section, while the semiconductor device can also be made lighter than by using a glass-fitted cap.
However, when the sealing resin is filled into the cavity 102 by potting, etc. for resin sealing of the CCD 104 mounted in the cavity 102 of the ceramic package 100, it has been shown that bleed-out of the sealing resin occurs from the cavity 102 at the end face of the ceramic package 100. This bleed-out phenomenon is such that the sealing resin creeps up the walls of the cavity 102 and seep out at the end face of the ceramic package 100.
This sealing resin which has bled out from the end face of the ceramic package 100 is very difficult to remove completely even by washing.
For this reason, a frame-like ceramic barrier is provided along the edges of the cavity 102 of the ceramic package 100 to try to prevent bleed-out of the sealing resin due to the height of the barrier, or the amount of the sealing resin filling the cavity 102 is adjusted; however, even with these measures it has still not been possible to prevent the phenomenon of bleed-out of the sealing resin.
As a strategy for solving the above-mentioned problems of the prior art, Japanese Unexamined Patent Publication No. 61-292328 discloses provision of a resin flow control material layer made of silicon grease or silicon oil, instead of the aforementioned barrier, but this method has still been inadequate for preventing bleed-out of sealing resins.